FB19957253 (Crash on Hierarchical List children access from SwiftData inherited model) Again, thank you so much! I hope I gave enough informations, feel free to ask if I can do anything.

Thanks a lot for helping Ziqiao, i've made a small iOS App that shows the issue which is available here: https://github.com/fgirardey/SwiftDataInheritance The step to reproduce are: Create a collection named "Work" Create another collection name "Tech" that has "Work" as a parent Kill the app, relaunch and see the crash happening when List is accessing to \children through \.childrenOrNil.

Hi Ziqiao, I've tried with iOS 26 Beta 7 and since Beta 8 (landed tonight) on device (because my Xcode is stuck on iOS Beta 6, don't know why) and the problem is solved. I can now query CollectionItem with predicate that contains inherited properties. Now I have only got problems with accesses to the children property in List. When i got the following hierarchy and the SwiftUI view List access to the \Item.children property I got another kind of crash. Category: "Work" (parent: none) Category: "Tech" (parent: "Work") Thread 1: Fatal error: Never access a full future backing data - PersistentIdentifier(id: SwiftData.PersistentIdentifier.ID(backing: SwiftData.PersistentIdentifier.PersistentIdentifierBacking.managedObjectID(0x9872c0007ba42159 <x-coredata://E5407415-7D6A-4920-B910-6D0D39290E5E/CollectionItem/p1>))) with Optional(7639D151-5D48-46AC-AB2A-7F0F50919AC5) But I guess it's a different kind of problem now.

Here is the CollectionItem model: @available(iOS 26, *) @Model final class CollectionItem: Item { var name: String var icon: String? init( name: String, icon: String? = nil, parent: CollectionItem? = nil, timestamp: Date = .now ) { self.name = name self.icon = icon super.init(parent: parent) } } Do you really need such a complex solution? I'm not sure, what I want is to mix CollectionItem and LinkItem. Collections can have children, Links cannot. It's like a file system where a directory can have directories or files. So yeah it's a bit complex but this might not be that exotic. There is probably a better way to design this…